Braille - n. a system of writing for blind people in which letters are represented by raised dots
trial - n. a test of the quality, value, or usefulness of something
parallel - adj. moving in the same direction, side-by-side or taking place at the same time
hard of hearing - adj. relating to or having a defective but working sense of hearing
caption - n. a sentence or group of words that is written on or next to a picture to explain what is being shown